Selenium status in the body and cardiovascular disease: a systematic review and meta-analysis

Abstract

Background: Both experimental and observational studies have provided conflicting evidence on the associations of selenium with incidence and mortality of cardiovascular disease (CVD). The aim of this study was to evaluate the association between selenium status in the body and incidence and mortality of CVD by performing a systematic review and meta-analysis of observational studies and randomized controlled trials. Methods: A systematic search for articles in MEDLINE (Ovid), Embase, Web of Science (Thomson Reuters) and Cochrane library (Wiley) was conducted. Thirteen of the 1811 articles obtained from the databases met our inclusion criteria and were considered in the final analysis. The effect sizes were presented as weighted relative risk (RR) and 95% confidence intervals (CIs) using random-effects model. To detect dose-response relationships, we used meta-regression. Results: Overall, there was a reduced risk of CVD incidence (RR ¼ 0.66; 95% CI: 0.40-1.09) and mortality (RR ¼ 0.69; 95% CI: 0.57-0.84) in physiologically high selenium status compared to low selenium status in the body. There was a 15% (RR ¼ 0.85, 95% CI: 0.76-0.94) decreased risk of CVD incidence per 10 mg increment in blood selenium concentration. In addition, a statistically significantly nonlinear dose-response relationship was found between CVD mortality and increased blood selenium concentration with the lowest risk at the 30-35 mg increment in blood selenium. Conclusions: Physiologically high selenium levels in the body are associated with decreased risk for CVD incidence and mortality, however, people should be cautious about the potential harmful effects from excessive intake of selenium.

The rationale for selenium supplementation in patients with autoimmune thyroiditis, according to the current state of knowledge

“…A recent meta-analysis reported a 50% increase in Se concentration to be associated with 24% reduction in the risk of developing ischaemic heart disease [78]. A similar conclusion was drawn by a study that reported a reduced risk of CVD (RR: 0.66, 95% CI: 0.40-1.09) and mortality (RR: 0.69, 95% CI: 0.57-0.84) in individuals with high Se status [79]. Also, UK and Denmark PRECISE randomised, double-blinded, placebo-controlled, clinical trials explored the effects of Se supplementation on total cholesterol (T-C) and non-HDL cholesterol [80,81].…”

Selenium in Human Health and Gut Microflora: Bioavailability of Selenocompounds and Relationship With Diseases

“…Metaanalysis involving 16 prospective studies demonstrated an inverse relationship between Se status and cardiovascular risk (43). Likewise, a systematic review with meta-analysis involving 13 studies revealed that high physiological levels of Se are associated with lower incidence and lower mortality from cardiovascular disease (CVD) (44). In another meta-analysis in which more than 40 thousand participants in randomized clinical trials were included, the authors found that Se supplementation decreases the serum levels of C-reactive protein and increases the levels of GPX, suggesting a positive effect on reduction of inflammation and oxidative stress in cardiovascular diseases (45).…”

A Comprehensive Review on Selenium and Its Effects on Human Health and Distribution in Middle Eastern Countries

“…Deprivation of Se was strongly correlated with cardiomyopathy occurring in countries with significantly reduced Se intake [104]. Multiple studies have been conducted to evaluate Se's effect on CVD risk [105][106][107].…”